public class Example4_5{
  public static void main (String args[]){
	Rect ractangle = new Rect();
	ractangle.width = 109.87;
	ractangle.height = 25.18;
	double area=ractangle.getArea();
	System.out.println("矩形的面积："+area );
	Lader lader = new Lader();
	lader.above = 10.798;
	lader.bottom = 156.65;
	lader.height = 18.12;
	area = lader.getArea();
	System.out.println("梯形的面积："+area);
	}
} 
